Zimbabwe ? Prime Minister Morgan Tsvangirai left the hospital bandaged and mourning his wife Saturday after a car crash that his supporters blamed partly on insufficient security provided by President Robert Mugabe.

Tsvangirai’s Movement for Democratic Change called for an investigation into the collision with a truck carrying U.S. aid, but cautioned against concluding that it was the latest assassination attempt against the longtime opposition leader.

Friday’s crash nonetheless “could have been avoided” if Tsvangirai had the kind of motorcade that usually travels with Mugabe, said Tendai Biti, the country’s new finance minister and Tsvangirai’s No. 2 in the party. An MDC official who was traveling with Tsvangirai said the premier’s Toyota Land Cruiser was accompanied by three vehicles with MDC security and one with Mugabe’s agents, but not the kind of motorcade with dozens of cars and motorcycles that usually transports the president.

The official spoke on condition of anonymity because of the sensitivity of the issue.